Talk:Potamotrygonidae

External links modified
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 * Added archive https://web.archive.org/web/20131226003829/http://www.ufrgs.br/ni/NIv11n04/NIv11n4-693-737.pdf to http://www.ufrgs.br/ni/NIv11n04/NIv11n4-693-737.pdf

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Cheers.— InternetArchiveBot  (Report bug) 21:45, 15 January 2018 (UTC)

stingray ?venom vs toxin
It is important to note that stingrays are not venomous, that is, they do not have venom glands like venomous snakes. The pain from the sting is caused by toxins in the skin, which covers the spine, and thereby enters the wound. Being stuck by the fleshy spines on the tail is also very painful but not as painful as the cartilaginous spine. Therefore the word "venom" should be substituted throughout with "toxin". For the same reason we say that snakes are venomous, not poisonous. because they do have venom glands.Drstingray (talk) 23:27, 28 January 2021 (UTC)